1. Field of the Invention
The present invention relates to a carburetion type burning apparatus enabling to generate an alarm when an abnormal state takes place by deposition of tar and undesired substance on the inner wall of a carburetion chamber.
2. Description of Prior Art
As an example of conventional carburetion type burning apparatuses, there has been known one described in Japanese Unexamined Patent Publication No. 98710/1982. In such a burning apparatus, when kerosene evaporates in a carburetion chamber in burning operation, polymerization of molecules constituting kerosene at the temperature causing evaporation and a small amount of residue (impurities) gradually produce tar (carbide), which deposites on the inner wall of the carburetion chamber as the time in the burning operation goes on.
Accumulation of the tar on the carburetion chamber causes clogging of a passage for fuel gas evaporated in the carburetion chamber. As a result, an amount of the fuel gas to be produced becomes small, hence the quantity of burning is small whereby faulty burning may occur. To prevent such disadvantage, the conventional burning apparatus is provided with an additional burning device for burning the tar deposited on the carburetion chamber at a temperature higher than the ordinary carburetion temperature to remove the tar.
An amount of tar deposited on the carburetion chamber largely varies depending on impurities contained in kerosene to be used. Further, time needed for burning to remove the tar is also various because of characteristics of individual burning apparatuses. In many cases, the burning operation has been carried out at the beginning or the last in a period for use. However, the burning operation has often been required even in being used in the case that kerosene containing much impurities has been used.
It is, however, difficult to judge by eyes an initial stage of the abnormal burning condition that tar begins to accumulate on the carburetion chamber to reduce the quantity of burning. As a result, burning operation is continued under abnormal burning condition for a long time until the abnormal burning operation caused by the deposition of much tar becomes visible by eyes. This takes place problems of production of toxic gas, soot and bad smell, and that it takes a long time to remove tar accumulated in thick on the carburetion chamber by additional burning.